The term jerk refers to a way that meat is seasoned and cooked. It is said to come from the word charqui, a Spanish term for dried meat. It doesn't just refer to chicken, but can also include beef, pork, goat, and fish. The traditional style utilizes a marinade that includes pimento, often called allspice, and Scotch Bonnet peppers. The meat is marinated and then slow smoked over pimento wood.
Early Europeans mistook the pimento berries for black pepper and named them pimento, which is the Spanish word for pepper.
The style of cooking jerk chicken goes back over 2500 years ago, to the Arawak Indians who settled Jamaica. The ancient technique they used can still be seen today in the form of jerky.
In 1492 Columbus claimed Jamaica for Spain and enslaved the Arawak Indians. The vast majority of Indians eventually perished (though some escaped into the mountains), and were replaced by African slaves. After the British established colonial rule in the 1600's, some of the slaves escaped and hid in the Blue Mountains. They became known as Maroons. Survival was not easy as meat was scarce on the island, and wild boar became the primary source of food. The Maroons dug holes in the ground, filled them with charcoal, and buried the meat in holes, which they covered so as not to produce smoke and attract attention. To this day Jamaican jerk chicken can still be found cooked in pits according to tradition.